title: Acidification and buffering mechanisms in acid sulfate soil wetlands of the Murray-Darling Basin, Australia.
abstract: The acid generation mechanisms and neutralizing capacities of sulfidic sediments from two inland wetlands have been studied in order to understand the response of these types of systems to drying events. The two systems show vastly different responses to oxidation, with one (Bottle Bend (BB) lagoon) having virtually no acid neutralizing capacity (ANC) and the other (Psyche Bend (PB) lagoon) an ANC that is an order of magnitude greater than the acid generation potential. While BB strongly acidifies during oxidation the free acid generation is less than that expected from the measured proton production and consumption processes, with additional proton consumption attributed to the formation of an acid-anion (chloride) FeIII (oxyhydr)oxide product, similar to akaganéite (Fe(OH)2.7Cl0.3). While such products can partially attenuate the acidification of these systems, resilience to acidification is primarily imparted by sediment ANC.
authors.affiliation: Department of Agricultural Sciences, La Trobe University, Bundoora, Australia, 3086.
authors.forename: Fiona
authors.initials: F
authors.lastname: Glover
authors.forename: Kerry L
authors.initials: KL
authors.lastname: Whitworth
authors.forename: Peter
authors.initials: P
authors.lastname: Kappen
authors.forename: Darren S
authors.initials: DS
authors.lastname: Baldwin
authors.forename: Gavin N
authors.initials: GN
authors.lastname: Rees
authors.forename: John A
authors.initials: JA
authors.lastname: Webb
authors.forename: Ewen
authors.initials: E
authors.lastname: Silvester
mesh_terms: D001315:Australia; D005290:Ferric Compounds / Q000737:chemistry; D005618:Fresh Water / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D010084:Oxidation-Reduction; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000737:chemistry*; D013431:Sulfates / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000737:chemistry*; D053833:Wetlands
chemical_list: D005290:Ferric Compounds; D012987:Soil; D012989:Soil Pollutants; D013431:Sulfates; D014874:Water Pollutants, Chemical; C000499:ferric oxide